Trump, Obama & Clinton Dragged Into Death Threat Investigation

President Obama, Donald Trump and Hillary Clinton may not all be square politically, but they're all in the same boat, because they're now part of an LAPD death threat investigation.

Law enforcement sources tell us cops have been on the case since September. According to docs -- obtained by TMZ -- a woman sent a message on the Church of Scientology website saying, "I hate the United States Because I never get anything I want 100%. I hate President Obama, Hillary Clinton, Donald Trump, all Gerontologists ..."

She goes on ... "This is why I will gladly serve you to the satan ..."

Cops are not saying how serious it is, but they're calling it a death threat investigation. They've served a search warrant and believe they know the identity of the suspect, but she hasn't been arrested.